Thermostatic switch mechanism



June 27, 1933. F. J. KUMP THERMOSTATIC SWITCH MECHANISM 2 Sheets$heet 2 Filed March 18, 19-31 Patented June 27, 1933 FERDINAND J. KUMP, OF GLENDALE, LONG ISLAND, NEW YORK THERMOSTATIC SWITCH MECHANISM Application filed March 18, 1931. Serial No. 523,591.

This invention aims to provide a novel thermostatic switch mechanism for governing the operation of an aquarium heater, and to provide novel means whereby an operator may adjust the switch mechanism to change the temperature of the water in the aquarium.

It is within the province of the disclosure to improve generally and to enhance the utility of devices of that type to which the invention appertains.

With the above and other objects in view, which will appear as the description proceeds,the invention resides in the combination and arrangement of parts and in the details of construction hereinafter described and claimed, it being understood that changes in the precise embodiment of the invention herein disclosed, may be made within the scope of what is claimed, without departing from the spirit of the invention.

In the accompanying drawings:

Figure 1 shows in vertical section, an aquarium wherein the device forming the subject matter of this application has been mounted, the mechanism being in elevation, with parts broken away;

Figure 2 is a circuit diagram;

Figure 3 is a vertical section of the switch mechanism, the heater being omitted;

Figure 4 is a vertical section on the line 44 of Figure 3;

Figure 5 is a horizontal section on the line 5-5 of Figure 3; i

Figure 6 isa horizontal section on the line 66 of Figure 3;

Figure 7 is a view like Figure 6, but showing the switch members separated to break the heat circuit.

The device forming the subject matter of thisapplication preferably is made of metal throughout, saving where insulating material may be required for electrical reasons. The device comprises a support, which, as a whole, is marked by the numeral 1.

The support 1 includes a horizontal, boxlike casing 2, surmounted by a removable lid 3. The lid 3 has a downwardly extended flange 4, disposed about three sides'of the casing 2. At one end, the lid 3 has a resilient tongue 5, adapted to engage a boss 6 on the corresponding end of the casing 2. At its opposite end, the lid 3 has an angular finger 15 engaged in an opening 25 in the corresponding end 7 of the casing 2. The end 7 of the casing 2 may be made of insulating material, and it is held in the casing 2 by se curing members 8.

The end 7 of the casing 2 is supplied with an opening 9, adapted to receive a sheath 10 which carries conductors 11 and 30. The conductor 11 is connected to a bindingpost 12, which holds a first spring switch tongue 14 on an insulating block 16, the block being secured in the casing 2 by attaching elements 17.

Along the inner surface of the first switch tongue 14 extends an insulating strip 18 which is secured to the switch tongue. The switch tongue 14 and the insulating strip 18 have a depending end19 carrying a contact terminal 20 (Figure 6) held by the resiliency of the tongue 14 against a contact terminal 21 on a second spring switch tongue 22 which extends across the depending end 19 of the strip 18 of the first switch tongue 14, as Fig ure 3 will show. The second switch tongue 22 is disposed below the first switch tongue 14 in parallel relation thereto, and one end of the second switch tongue 22 is held by a binding post 23 on the insulating block 16.

One end of a conductor 24 (Figure 2) is connectedto the binding post 23, and therefore to the second switch tongue 22. The conductor 24 is connected to one end of an electric heater 26 disposedin a transverse, horizontal, hermetic, tubular foot 27, mounted intermediate its ends (Figure 1) on the lower end of a hollow arm 28, in the form of a tube. The upper end of the arm 28 is connected by nuts 29 (Figure 3) to the bottom of the casing 2. Tothe opposite end of the heater 26 (Figure 2) is connected the conductor 30, hereinbefore mentioned, the conductors 30 and 24 extending upwardly through the hollow arm 28, and both of the conductors 30 and 24 extending outwardly through the sheath 10, to a source of electrical energy (not shown).

A depending tubular housing 31 is rigidly mounted in the bottom of the casing 2 (Figure 3) and is located near to one end of the casing. A removable plug or foot 32 is held by a securing device 33 in the lower end of the housing 31. The housing 31 is supplied with a side hole 34, located a little way above the foot 32 (Figure 4).

The lower end of a laterally flexible thermostat 35 is mounted in the foot 32, and the thermostat has an extension 36 which is prolonged upwardly through the housing 31,

into the casing 2. The extension 36 of the thermostat is equipped at its upper end with an insulating head 37 against which the contact terminal 21 (Figure 6) of the second switch tongue 22 bears, owing to the resil iency of the said switch tongue.

Within the casing 2, above the switch tongues 14 and 22, is located a horizontal partition or bearing 38 held in place by socuring elements 39 (Figures 4 and 1), the partition being provided at one end with a reduced projection 40 (Figure 5) engaged in the opening 25 (Figure 3) of the endmemher 7 of the casing 2.

A vertical shaft 41 is mounted to rotate in the partition 38 and is located near to the free ends of the switch tongues-22 and 14. A radial index 42 is located above the partition 38 and is secured at one end of the shaft 41. The opposite end of the index 42 (Figure 5) cooperates with a scale 43 inscribed on the partition 38-at one end thereof. The shaft 41 carries transverse arm 44 disposed below the partition 38, and located in the path of movement of the first switch tongue 14, as a comparison of Figures 3, 6 and 7'will show. The shaft 41 is provided with an operating member, which may be a knob 45, arranged above the partition 38 and below the removable lid 3.

In Figure 1, the numeral 46 marks a hookshaped hanger secured to'a collar 47 which isfrictionally held on the hollow arm 28 for adjustment circumferentially of the arm and longitudinally of the arm. he device may be mounted in an aquarium 49 in any desired way. For instance, a cross bar 48 may be laid on the upper edge of the aquarium, and

the hanger 46 may be engaged with the cross bar, the heater 26 being suspended in the water. of the aquarium, andth-e housing 31 being extended downwardly into the water far enough, so that the water can enter the housing 41 through the opening 34 of Figure '5 4 and come into direct contact with the thermostat 35.

Assume that current is flowing through the conductors 11 and 30, and that the-switch members 22 and 14 are in the position of Figure 6, with the contacts 20 and 21 touching each other. Then there is established the heating circuit of Figure 2, the said circuit comprising the conductor 11, the switch tongue 14, the contact 20, the contact 21, the switch tongue 22, the conductor 24, the electric heater 26, and the conductor 30. Thus the temperature of the water 50 in the aquarium 49 will be raised by the action of the heater 26.

As the temperature of the water 50 in the aquarium 49 rises, the thermostat 35 will tend to swing in the direction of the arrow A in Figures 4, 6 and 7.v At first, the resilient switch-tongues 14 and 22 will follow the thermostat as it flexes, and the heating circuit of Figure 2 will be maintained in a closed position. Ultimately the insulating member 18 (Figure 7) on the switch tongue 14 will come into contact with the arm 44 on the shaft 41, and the swinging movement of the switch tongue 14 will be arrested. The switch tongue 22, however, will continue to move in the direction of the arrow A, along with the head 37 on the extension 36 of the thermostat 35, and the contact 21 of the switch tongue 22 will be spaced from the contact 20 of the switch tongue 14, thereby opening the heating circuit of Figure 2, and putting the heater 26 out of operation. As the water 50 in the aquarium cools off, the thermostat 35 will swing in a direction opposite to that indicated by the arrow A in Fig ures 4 and 7, thereby bringing the contact 21 again into engagement with the contact 20, the heating circuit being closed. Thus, within the limits allowed for thermostats, the water 50 inthe aquarium will be kept at a uniform temperature. I

Suppose that the operator takes off the lid 3 and rotates the shaft 41 clockwise, by means of the knob 45. This operation will move the arm 33 (Figure 6) on the shaft 41 nearer to the spring switch tongue 14 and arrest the movement of the said switch tongue, in the direction of the arrow A, at an earlier stage, the contacts 20 and 21 being spaced'apart, and the heating circuit being opened accordingly. The operator, therefore, has at his command a means whereby he can regulate the length of time that the heater 26 is in operation, before the contacts 20 and 21 are separated, as in Figure 7 The index 42 of Figure 5, cooperating with the scale 43, shows at a glance, the, position of the arm 44 with respect to the switch member 14, and, therefore, whether the water 50 in the aquarium is being heated to a high temperature or to a low temperature.

Having thus described the invention, what is claimed is:

Thermostatic switch mechanism embodye ing aboxlike casing, a partition in the casing and provided with a scale, a shaft journaled in the partition and provided with an arm located below the partition, an index carried by the shaft and coacting with the scale,

means on the shaft, above the partition,

whereby the shaft may be rotated, approxi mately parallel, resilient, first and second switch tongues located in the casing, below the partition, and connected at one end to the casing, the arm being located in the path of movement ofthe first switch tongue, the 

